首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   192111篇
  免费   1759篇
  国内免费   141篇
耳鼻咽喉   1282篇
儿科学   6971篇
妇产科学   3121篇
基础医学   18781篇
口腔科学   1895篇
临床医学   13420篇
内科学   35234篇
皮肤病学   997篇
神经病学   18000篇
特种医学   9514篇
外科学   31458篇
综合类   2385篇
预防医学   18492篇
眼科学   3101篇
药学   10537篇
中国医学   666篇
肿瘤学   18157篇
  2023年   126篇
  2022年   234篇
  2021年   426篇
  2020年   217篇
  2019年   345篇
  2018年   22275篇
  2017年   17642篇
  2016年   19845篇
  2015年   1323篇
  2014年   1327篇
  2013年   1414篇
  2012年   8024篇
  2011年   22140篇
  2010年   19425篇
  2009年   12008篇
  2008年   20488篇
  2007年   22814篇
  2006年   1675篇
  2005年   3407篇
  2004年   4547篇
  2003年   5486篇
  2002年   3584篇
  2001年   466篇
  2000年   556篇
  1999年   377篇
  1998年   465篇
  1997年   406篇
  1996年   265篇
  1995年   281篇
  1994年   235篇
  1993年   189篇
  1992年   138篇
  1991年   182篇
  1990年   204篇
  1989年   167篇
  1988年   132篇
  1987年   111篇
  1986年   83篇
  1985年   75篇
  1984年   68篇
  1983年   58篇
  1982年   59篇
  1981年   40篇
  1980年   76篇
  1978年   32篇
  1974年   30篇
  1938年   60篇
  1934年   30篇
  1932年   57篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
Intraosseous ganglia of the glenoid are rare, and their etiology is unknown. This report describes a case of an intraosseous ganglion about to cause fracture of the glenoid. The patient was a 61-year-old woman with a painful left shoulder with a limited range of motion. Her symptoms did not improve after non-operative treatment. Arthroscopic examination showed a cartilage defect and erosion in the posteroinferior portion of the glenoid, behind which computed tomography (CT) showed a cystic lesion of the glenoid. There was no communication between the cyst and the joint space. The patient was treated by curettage and an autogenous cancellous bone graft from the iliac crest. Two years after the operation, the patient was almost free from pain, and CT showed good integration of the bone graft.  相似文献   
102.
103.
104.
105.
106.
107.
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death.  相似文献   
108.

Background  

It has been observed that ras-transformed cell lines in culture have a higher phosphatidylcholine (PC) biosynthesis rate as well as higher PC-degradation rate (increased PC-turnover) than normal cells. In correspondence to these findings, the concentrations of the PC-degradation product lyso-phosphatidylcholine (LPC) in cancer patients were found to be decreased. Our objective was the systematic investigation of the relationship between LPC and inflammatory and nutritional parameters in cancer patients. Therefore, plasma LPC concentrations were assessed in 59 cancer patients and related to nutritional and inflammatory parameters. To determine LPC in blood plasma we developed and validated a HPTLC method.  相似文献   
109.
110.
A 36-year-old man was admitted to a hospital with complaints of fever, polyarthralgia and dyspnea. Erythema was observed on his face, extensor surface of the fingers and extremities, and a chest X-ray revealed massive bilateral pleural effusion. He had no sign of myopathy at this point. Pleural fluid was proved to be exudative and contained extremely high levels of hyaluronic acid. He was also complicated with interstitial pneumonitis and was given a pulse therapy with methyl prednisolone followed by daily administration of 55 mg prednisolone (PSL). Twenty days after the commencement of the therapy, pleural effusion decreased but muscle weakness gradually appeared, accompanied by elevation of myogenic enzymes. Myogenic changes on electromyogram, and irregularity of the muscle fibers with slight inflammatory cell infiltrates in a biopsy specimen were demonstrated. He was transferred to our hospital, and a diagnosis of dermatomyositis was made. Later, pleural effusion waxed and waned depending on the dosage of PSL, but no other causative disorder was demonstrated by extensive examinations. This case indicates that the pleuritis could be one of the vasculitic manifestations of dermatomyositis.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号